06 Cummins code p0148 no power

coorsman2005

coorsman2005

i like beer
As title says. Code p0148 no power at high rpms pops out the exhaust. It did throw a crank pos sensor. Put in a known good one that code stopped. Heres some things i have done. I ran the valve lash just for the hell of it. They were a little loose not bad there at spec now.
Changed fca with known good one. Installed railplug. Crank pos sensor

I hooked up my rail gauge and when it first starts it spikes up to like 15k. Then slowly drops to around 8k and stays. Under full throttle it will hit 10k. Then when you let off it will spike to 12k. But it idles at 8 k constant. In neutral if you rev it it will hit 15k but not when driving

The owner of the truck replaced the lp with a stock in tank. And put new fuel filter and air filter.

Truck is bone stock besides strait pipe.

What are some thoughts of what could cause this
 
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coorsman2005 said:
...I hooked up my rail gauge and when it first starts it spikes up to like 15k. Then slowly drops to around 8k and stays. Under full throttle it will hit 10k. Then when you let off it will spike to 12k. But it idles at 8 k constant. In neutral if you rev it it will hit 15k but not when driving...
Click to expand...
Is 15k rail pressure the MAX you have at any time?
If so, you have a leak somewhere.

I'd suspect CP3 or injectors.

Mark.
 
Yep. And 15k is at startup. Like 12 after that. At full throttle the most i have seen is 10. Until you let off then it spikes 12.
 
Might be a silly question but have you checked the oil level to see if its rising or a good thing to do would be a injector return fuel test.
 
Unplug the rail pressure sensor with the truck running and the rail pressure should max out.
 
Gwoody said:
Unplug the rail pressure sensor with the truck running and the rail pressure should max out.
Click to expand...


I did unplug the fca with no change. Also u swapped with a known good fca. Could the cp3 be taking a dump. I have never been around a truck with a bad cp3. What do they start out doing. I assumed they just totally quit like most other pumps.
 
My dad’s CR lost a CP3 due to a plugged inlet screen on his aftermarket fuel pump. Low on power but still had enough fuel flow to crank normally and run. Just no damn power.
New CP3 restored years of slowly reduced power. Truck runs strong as ever now, some 375k later.
 
Tinkering with this truck again. When I first started the truck this morning. Rail psi was idiling around 5k. I unplugged the fca. It spiked up full psi 25-30k. Plugged it back in psi slowly dropped back to normal.

Took the truck for a drive. As it hit operating temp it lossed power and rail psi. At full throttle it wouldn’t even hit 5k. When I got to my house I unplugged the fca. With no change in rail psi 3-5k idiling. Reved it up plugged in or unplugged 8 k max.

What you guys think now.
 
Hell, we talked about those in my last phone call and you just now looked at them?
At any rate, glad it's cooperating. :)

Mark.
 
Not adequately tightened, then they loosened themselves with heat cycles.
It's actually fairly common, especially with the 5.9 connector tubes, as they are a bit flimsier.

Mark.
 
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